1. Field of the Invention
This invention relates to a receptacle for storing used stencils.
2. Description of the Prior Art
Box-shaped receptacles have been used for storing used stencils. Such receptacles have a base, a pair of long straight sides and a pair of short straight sides, and are without a lid, and receive and store used stencils discharged from a printing machine.
FIG. 19 of the accompanying drawings shows the configuration of a lithographic printing machine 34 , which comprises a document reader 34a, a stencil perforating section 34b, a printing drum 1, a sheet tray 34c, a sheet feeder 34d, a stencil discharging section 34e, and so on. A used stencil receptacle 5 constitutes part of the sheet discharging section 34e. When the printing machine 34 starts operating in an automatic stencil perforating mode, the printing drum 1 is rotated in the direction opposite to that used in the printing operation as shown in FIG. 16, so that a used stencil will be received in the used stencil receptacle 5. In this state, a stencil take-up belt 3, which is kept away from the printing drum 1 with a stencil take-up belt 2 during the printing operation, is moved to a position shown by the solid line from the position shown by the dashed line. In other words, the stencil take-up belt 3 comes into contact with the printing drum 1. Then, a clamp (not shown) holding the leading edge of a stencil 4 frees the stencil 4.
A surface of the stencil take-up belt 3 in contact with the printing drum 1 rotates in a direction opposite to that of the printing drum 1, so that the trailing edge of the used stencil 4 is scooped up by the stencil take-up belt 3. The stencil 4 is then drawn into the space between the stencil take-up belts 2 and 3, is stripped off the printing drum 1, is continuously conveyed via the stencil take-up belts 2 and 3, and is put into the used stencil receptacle 5.
In addition to the foregoing method, several methods are available so as to strip the stencil from the printing drum 1. In one method, the used stencil 4 is stripped from the printing drum when the clamp frees the leading edge of the used stencil 4, without reversing the rotational direction of the printing machine 1. In another method, stencil take-up rollers which are disposed in the used stencil receptacle are utilized in place of the combination of the stencil take-up belts 2 and 3 and the used stencil receptacle. In any case, the used stencil is discharged into the used stencil receptacle 5.
The discharged stencils 4 fold naturally and are stacked in the used stencil receptacle 5, and are compressed by a pressing member 6 at appropriate times so as to store as much of the stencils 4 as possible.
The used stencil receptacle 5 full of the used stencils 4 is detached from the printing machine, so that the used stencils 4 can be discarded. The used stencil receptacle 5 is returned to the original position in the printing machine 34.
The used stencil receptacle 5 is box-shaped as shown in FIG. 17, and includes a rectangular base 5-1, a pair of short straight sides 5-2 and 5-3, and a pair of long straight sides 5-4 and 5-5. The used stencil receptacle 5 has an open top. The long straight side 5--5 has a grip 5-6.
It is assumed that each used stencil 4 has a size W in a direction parallel to the rotary axis of the printing drum 1, and a size L in a direction in which the used stencil 4 is conveyed. In this case, W is larger than L. Thus, the base 5-1 of the used stencil receptacle 5 is rectangular with size W.times.L. The used stencil receptacle 5 is long in the direction orthogonal to the direction in which the used stencil is paid.
The height of the used stencil receptacle 5 is determined on the basis of a height H of the maximum number of used stencils stacked therein. For instance, when a maximum number of A3 size stencils are stacked in the used stencil receptacle, W is 320 mm, L is 120 mm, and H is 120 mm.
The used stencil receptacle 5 full of used stencils is removed from the printing machine, and is emptied. The used stencil receptacle 5 will be returned into the printing machine 34.
Referring to FIGS. 17 to 19, when removing the used stencil receptacle 5, it is moved in a direction shown by the arrow 30 which is the same as the stencil feeding direction. Specifically, an operator standing before the front side of the printing machine moves the used stencil receptacle 5 to the left or right. The grip 5-6 on the side 5--5 is used when detaching the used stencil receptacle 5. As shown in FIG. 18, the used stencil receptacle 5 is secured at its pulling side by a holding member 31. Thus, first of all, the holding member 31 is opened as shown by the arrow 33 using a shaft 32 as a fulcrum, in the direction 30. Then, the used stencil receptacle 5 is pulled out of the printing machine 34 by pulling the grip 5-6.
In order to secure space for opening the holding member 31 and space for removing the used stencil receptacle 5 from the printing machine, a sorter 35 used in conjunction with the printing machine 34 has to be located at a position which is clear of the printing machine 34 by a distance K. The printing machine 34 and the sorter 35 constitute a printing system.
In the printing machine 34 of the prior art, the used stencil receptacle 5 is designed to be laterally moved (i.e. in the stencil feeding direction), viewed from an operator standing in front of the printing machine 34. Therefore, the operator extends his or her left arm and twists himself or herself so as to pull the used stencil receptacle 5 to the left. Further, since the used stencil receptacle 5 is pulled in the direction shown by the arrow 30, the sorter 35 should be kept away from the printing machine 34 by the distance K so as to retain enough space for pulling the holding member 31 and the used stencil receptacle 5.
Now, it is assumed that the used stencils are discharged from the receptacle 5 into a trash container. When the trash container has an opening whose size is larger than W.times.L, the used stencil receptacle 5 is simply reversed so that its contents will fall into the trash container by their own weight. However, large trash containers having such a large opening are not so popular. As shown in FIG. 20, a trash container 7 in wide use usually has an opening whose size is W'.times.W' and a height larger than W. The size W'.times.W' is slightly greater than the smaller sectional area with size L.times.L of the used stencils stacked in the used stencil receptacle 5.
When the used stencil receptacle 5 is appropriately reversed using an axis O--O as the center of rotation, used stencils 4 may not smoothly pass through the entrance of the trash container 7. Further, used stencils 4 sometimes remain stuck onto the used stencil receptacle 5, and are slow to fall into the trash container 7.
In order to overcome the foregoing problems, the operator has to grasp the used stencils 4, turn the used stencil receptacle 5 upside down so as to discharge the used stencils 4 into the trash container 7 with the longer side of the used stencils kept vertical. Sometimes, the used stencils 4 taken out of the used stencil receptacle 5 should be appropriately folded before they are discharged into the trash container 7.